This invention relates to a gas charging fixture for pressurizing a shock absorber, strut, gas spring or the like. More particularly, in one embodiment, the invention relates to a charging fixture which serves additionally to compress the shock in the area of the inner cylinder head seal for enhancing the sealing action of the seal.
Heretofore, shock absorbers have been pressurized by drilling a hole in the outer wall of the shock cylinder. After pressurizing the cylinder through the drilled passage, the passage is sealed by pressing a plug or ball into the passage. Alternatively, the passage may be sealed by welding after the passage has been closed by the plug.
This method requires several operations such as drilling and welding which, at best, impose additional expense and the chance that metal chips or weld contaminants may be introduced into the damper assembly.
To overcome these disadvantages, another method of pressurizing shock absorbers applies gas pressure against the piston rod wiper seals, forcing the seal away from the intermediate cylinder head and permitting the gas to pass into the shock. The present invention provides a gas charging fixture for use with such a method. More particularly, a particular embodiment of the charging fixture serves to deform the shock absorber casing in order to enhance the sealing action of the inner cylinder head seal of the shock absorber.